Apple also includes the adapter in the box with the iPhone 8, iPhone 8 Plus, and iPhone X, but more evidence has emerged today that suggests that trend will soon end.
Cirrus Logic, a supplier for the adapter, has apparently "confirmed" that the dongle won't be bundled with Apple's widely rumored trio of new iPhones expected next month, according to a Barclays research note.
Barclays already anticipated this would be the case earlier this year.
"Reported a beat but gave mixed guidance with revenue below but earnings ahead. Cirrus didn't update its FY19 guide… but they did finally confirm the dongle loss, adding more support for our below estimates," the research note reads.
Apple routinely says it is pushing towards a "truly wireless future," and the headphone jack adapter has always been a stopgap amid that transition, so if Apple chooses not to include it in the box, it shouldn't really come as a surprise. Rumors suggest new iPads will also lose the headphone jack and adapter.
Not everyone prefers wireless headphones, like AirPods, however, so if true, the removal of the adapter will almost certainly generate some controversy.
Apple will likely continue to sell the adapter as a standalone accessory for $9, which is cheap by its standards, so customers at least won't be forced to pay too much extra for the adapter if it is indeed removed from the box this year.
The adapter is also available at resellers such as Best Buy, where nearly two years later, it is the retailer's second-best selling Apple product in terms of units, so an argument could be made that Apple is removing the adapter too soon.
In a little over a month, we should find out for sure.